general_fact: 6819 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 6819 is 20457 / 3, and each digit is contained in the equation exactly once.
trivia: 6819 is an unremarkable number.
historical_date: September 1st is the day in 1836 that Narcissa Whitman, one of the first English-speaking white women to settle west of the Rocky Mountains, arrives at Walla Walla, Washington.